Sounds to me like you've got two perfectly good 25m ropes
is it a risk you'd take?
At Black Diamond, we don’t make ropes, and though we do have a drop tower, we don’t have the ability to perform official UIAA drop tests. However, I’m a curious guy, so I had my crack crew of engineers grab a few cords, mark them up with a Sharpie, and pull them in the tensile tester. As expected, the ropes always broke at the knot—the Sharpie’s middle mark seemingly having no effect on the strength of the cord during this test.
Tests done by the UIAA Safety Commission and some rope manufacturers have shown that marking ropes with liquids such as those provided by felt-tipped pens can damage them; even with those markers, sold specifically for marking ropes. The test results have shown a decrease of up to 50% of the rope strength, more correctly: of the energy absorption capacity of the rope (expressed by the number of falls in the standard test method in accordance with the UIAA Standard101).Therefore the UIAA Safety Commission warns against marking a rope with any substance that has not been specifically approved by the rope manufacturer of that rope.
How many people take big falls anyway, virtually no one.
It's falling on short lengths one should be more concerned for.
And the manufacturing controls on Class 3 PPE eliminate faults.
For the record, there would be no need to test the rope to destruction, a single standard drop test would be fine, after which you could continue using it.
There is a lot more to rope performance than 'it didn't snap'.